London: Men are grumpier than women, especially when it comes to getting their picture taken, a new study has found.

The study of more than 1,000 photographs in student yearbooks found that females far more likely to smile for the camera than males.

Psychologist Dr Nicolas Gueguen, who led the research, believes teenage girls associate smiling with attractiveness from role models such as actresses, female pop stars and models.

But boys, whose role models include rock bands and sport stars, tend to be sulkier and moodier."Women were more likely than men to smile expansively when photographed," daily quoted Dr Gueguen as saying.